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<div class="title">MQTTClient_willOptions Struct Reference</div>  </div>
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<p><code>#include &lt;<a class="el" href="_m_q_t_t_client_8h_source.html">MQTTClient.h</a>&gt;</code></p>
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Data Fields</h2></td></tr>
<tr class="memitem:aa5326df180cb23c59afbcab711a06479"><td class="memItemLeft" align="right" valign="top">char&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="struct_m_q_t_t_client__will_options.html#aa5326df180cb23c59afbcab711a06479">struct_id</a> [4]</td></tr>
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<tr class="memitem:a0761a5e5be0383882e42924de8e51f82"><td class="memItemLeft" align="right" valign="top">int&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="struct_m_q_t_t_client__will_options.html#a0761a5e5be0383882e42924de8e51f82">struct_version</a></td></tr>
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<tr class="memitem:a0e20a7b350881d05108d6342884198a5"><td class="memItemLeft" align="right" valign="top">const char *&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="struct_m_q_t_t_client__will_options.html#a0e20a7b350881d05108d6342884198a5">topicName</a></td></tr>
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<tr class="memitem:a254bf0858da09c96a48daf64404eb4f8"><td class="memItemLeft" align="right" valign="top">const char *&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="struct_m_q_t_t_client__will_options.html#a254bf0858da09c96a48daf64404eb4f8">message</a></td></tr>
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<tr class="memitem:a6a4904c112507a43e7dc8495b62cc0fc"><td class="memItemLeft" align="right" valign="top">int&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="struct_m_q_t_t_client__will_options.html#a6a4904c112507a43e7dc8495b62cc0fc">retained</a></td></tr>
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<tr class="memitem:a35738099155a0e4f54050da474bab2e7"><td class="memItemLeft" align="right" valign="top">int&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="struct_m_q_t_t_client__will_options.html#a35738099155a0e4f54050da474bab2e7">qos</a></td></tr>
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<tr class="memitem:a0e9356b973a918c25981982fe84e35d7"><td class="memItemLeft" >struct {</td></tr>
<tr class="memitem:afed088663f8704004425cdae2120b9b3"><td class="memItemLeft" >&#160;&#160;&#160;int&#160;&#160;&#160;<a class="el" href="struct_m_q_t_t_client__will_options.html#afed088663f8704004425cdae2120b9b3">len</a></td></tr>
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<tr class="memitem:a0d49d74db4c035719c3867723cf7e779"><td class="memItemLeft" >&#160;&#160;&#160;const void *&#160;&#160;&#160;<a class="el" href="struct_m_q_t_t_client__will_options.html#a0d49d74db4c035719c3867723cf7e779">data</a></td></tr>
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<tr class="memitem:a0e9356b973a918c25981982fe84e35d7"><td class="memItemLeft" valign="top">}&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="struct_m_q_t_t_client__will_options.html#a0e9356b973a918c25981982fe84e35d7">payload</a></td></tr>
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<a name="details" id="details"></a><h2 class="groupheader">Detailed Description</h2>
<div class="textblock"><p><a class="el" href="struct_m_q_t_t_client__will_options.html">MQTTClient_willOptions</a> defines the MQTT "Last Will and Testament" (LWT) settings for the client. In the event that a client unexpectedly loses its connection to the server, the server publishes the LWT message to the LWT topic on behalf of the client. This allows other clients (subscribed to the LWT topic) to be made aware that the client has disconnected. To enable the LWT function for a specific client, a valid pointer to an <a class="el" href="struct_m_q_t_t_client__will_options.html">MQTTClient_willOptions</a> structure is passed in the <a class="el" href="struct_m_q_t_t_client__connect_options.html">MQTTClient_connectOptions</a> structure used in the <a class="el" href="_m_q_t_t_client_8h.html#aaa8ae61cd65c9dc0846df10122d7bd4e">MQTTClient_connect()</a> call that connects the client to the server. The pointer to <a class="el" href="struct_m_q_t_t_client__will_options.html">MQTTClient_willOptions</a> can be set to NULL if the LWT function is not required. </p>
</div><h2 class="groupheader">Field Documentation</h2>
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<h2 class="memtitle"><span class="permalink"><a href="#aa5326df180cb23c59afbcab711a06479">&#9670;&nbsp;</a></span>struct_id</h2>

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          <td class="memname">char struct_id[4]</td>
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<p>The eyecatcher for this structure. must be MQTW. </p>

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<h2 class="memtitle"><span class="permalink"><a href="#a0761a5e5be0383882e42924de8e51f82">&#9670;&nbsp;</a></span>struct_version</h2>

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<p>The version number of this structure. Must be 0 or 1 0 means there is no binary payload option </p>

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<h2 class="memtitle"><span class="permalink"><a href="#a0e20a7b350881d05108d6342884198a5">&#9670;&nbsp;</a></span>topicName</h2>

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<p>The LWT topic to which the LWT message will be published. </p>

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<h2 class="memtitle"><span class="permalink"><a href="#a254bf0858da09c96a48daf64404eb4f8">&#9670;&nbsp;</a></span>message</h2>

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<p>The LWT payload in string form. </p>

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<h2 class="memtitle"><span class="permalink"><a href="#a6a4904c112507a43e7dc8495b62cc0fc">&#9670;&nbsp;</a></span>retained</h2>

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<p>The retained flag for the LWT message (see <a class="el" href="struct_m_q_t_t_client__message.html#a6a4904c112507a43e7dc8495b62cc0fc">MQTTClient_message.retained</a>). </p>

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<h2 class="memtitle"><span class="permalink"><a href="#a35738099155a0e4f54050da474bab2e7">&#9670;&nbsp;</a></span>qos</h2>

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<p>The quality of service setting for the LWT message (see <a class="el" href="struct_m_q_t_t_client__message.html#a35738099155a0e4f54050da474bab2e7">MQTTClient_message.qos</a> and <a class="el" href="qos.html">Quality of service</a>). </p>

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<h2 class="memtitle"><span class="permalink"><a href="#afed088663f8704004425cdae2120b9b3">&#9670;&nbsp;</a></span>len</h2>

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<p>binary payload length </p>

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<h2 class="memtitle"><span class="permalink"><a href="#a0d49d74db4c035719c3867723cf7e779">&#9670;&nbsp;</a></span>data</h2>

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<p>binary payload data </p>

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<h2 class="memtitle"><span class="permalink"><a href="#a0e9356b973a918c25981982fe84e35d7">&#9670;&nbsp;</a></span></h2>

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<p>The LWT payload in binary form. This is only checked and used if the message option is NULL </p>

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<hr/>The documentation for this struct was generated from the following file:<ul>
<li><a class="el" href="_m_q_t_t_client_8h_source.html">MQTTClient.h</a></li>
</ul>
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